In order to study the relationship between changes of soil fungal communities and its driving factors and winter wheat yield under straw mulching and nitrogen application, we adopted a split-plot field experiment that the main factor included no straw mulching (NSM) and straw mulching (SM), and two nitrogen application rates of 0 (N0) and 180 (N1) kg/hm² were used as the sub-factor. Soil samples were collected during wheat anthesis. We measured soil nutrients and analyzed the community structure and diversity of rhizosphere fungi by Illumina Miseq high-throughput sequencing technology. The results showed that wheat yield of straw mulching (SM) treatment was increased significantly by 40.3% than that of non-mulched (NSM) treatment. NSMN1 treatment significantly increased wheat yield by 75% compared to NSMN0. SMN1 treatment significantly increased wheat yield by 92% compared to SMN0. SM treatment significantly increased the contents of soil organic carbon (SOC), total nitrogen (TN), available nitrogen (AN), ammonium nitrogen (NH₄⁺-N), available phosphorus (AP) and available potassium (AK), but the soil nitrate nitrogen (NO₃^--N) content was reduced than that of NSM treatment. No matter whether straw was added or not, nitrogen application significantly increased the contents of soil TN, AN, NH₄⁺-N, NO₃^--N, AP and AK. Straw mulching increased the Chao1 index and Shannon index of wheat rhizosphere fungi, while Chao1 index and Shannon index were decreased in N1. Compared with NSM treatment, SM treatment significantly increased the relative abundance of Basidiomycota and decreased the relative abundance of Mortierellomycota, but there was no significant difference in the relative abundance of Ascomycota. NSMN1 treatment significantly increased the relative abundance of Ascomycota, while the relative abundance of Basidiomycota and Mortierellomycota decreased significantly. SMN1 treatment significantly decreased the relative abundance of Ascomycota and increased the relative abundance of Basidiomycota, the relative abundance of Mortierellomycota decreased, but the difference was not significant. At the genus level, SM treatment significantly increased the relative abundances of Psilocybe, Curvularia and Nigrospora, and significantly decreased the relative abundances of Mortierella, Mycosphaerella, Sarocladium, Fusarium and Scytalidium compared with NSM treatment, while the relative abundance of Pyrenochaetopsis had no significant difference. Compared with NSM0, NSMN1 significantly increased the relative abundances of Mycosphaerella, Curvularia and Sarocladium, and significantly decreased the relative abundances of Mortierella and Scytalidium; SMN1 significantly increased the relative abundance of Psilocybe, Curvularia, Sarocladium and Scytalidium, and significantly decreased the relative abundance of Mortierella compared to SMN0. LEfSe analysis showed that Psilocybe, Curvularia and Mycosphaerella were the key fungal genera for straw mulching combined with nitrogen fertilizer. Based on RDA, soil SOC, AK, AP, AN, TN and NH₄⁺-N contents had significant or extremely significant effects on fungal community structure. Further analysis showed that Psilocybe, Curvularia and Scytalidium were associated with wheat yield under the conditions of straw mulching and nitrogen fertilization. In conclusion, straw mulching combined with nitrogen fertilizer is helpful to improve soil nutrient availability and wheat yield, and help optimize soil fungal community structure, which is of great significance for improving soil fertility and crop productivity in the hilly drylands of Sichuan.